Letters to the Editor
Mirror, Mirror, on the Floor…
Many of your readers are breeders who use bare-bottom
tanks for a variety of reasons. Because the bottoms are
transparent glass/acrylic the fish can see through it as
well as see their own reflection. This is confusing to the
fish and tends to make them nose into the bottom in an
attempt to get lower. Is there any suitable paint or other
application that can be used on the inside of the aquarium
bottom to make it unreflective as well as opaque?
While many breeders paint the outside of the bottom to
prevent the fish from seeing through it, you are correct that
with overhead lighting this can still lead to a confusing mirror
effect for the fish. Any of the marine epoxy paints that are used
to waterproof the inside of homemade plywood tanks should
work to coat the inside of the bottom, though you’ll need to
check with your paint dealer for the proper priming of glass
with these paints. An equally messy alternative that at least
does away with two-part epoxy mixtures is to spread a thin
layer of silicone aquarium adhesive over the glass, then press
a layer of sand or fine gravel into it. Let it cure a couple days,
then invert the tank and brush off any loose material that does
not immediately fall out. This will look more natural, and it
will be almost as easy to keep clean as bare or painted glass.
base rock in a marine tank will eventually become colonized
with a wide variety of organisms, including anaerobic
bacteria, porous rock in a freshwater aquarium will be
colonized by freshwater analogues.
I am unaware of any studies that measured nitrate reduction
or other parameters that would be affected by freshwater
live rock, but there aren’t that many even for marine live-rock setups. Unfortunately, common porous rocks are all
soluble, meaning that they can raise pH and hardness in any
aquarium, fresh or salt. However, they can provide functional
live rock for aquarists who use them in cichlid tanks or to
provide buffering capacity in extremely soft water.
Freshwater Live Rock?
I am the freshwater manager at a local pet store. I love
your magazine and read it daily. I have owned both salt-and freshwater tanks, mostly African cichlids—Malawi
mbuna. I was wondering if freshwater anaerobic bacteria
can be cultured in freshwater lace rock (or any rock for
that matter) as it is in marine live rock, and if so, can you
use this rock in any tank without the pH being offset by
The major difference between marine live rock and
freshwater live rock is that many of the aquarists using the
latter don’t know they are! The use of porous rocks like lace,
coral, lava, and tufa to build “reefs” in cichlid aquaria will
naturally produce freshwater live rock. In the same way that
All Aboard, TFH!
Your magazine has long been one of my fish resources.
I bring your magazine to work and read it every chance
I get, as in this picture, where I’m stopped in a siding,
waiting for another train to pass. I am a conductor/engineer
with Ottawa Valley Railway in North Bay, Ontario, Canada.
I have been a fishkeeper as long as I can remember. I
currently am maintaining six tanks throughout the house,
and I have about 40 others of various sizes in the garage
that have accumulated over the years for breeding, growing
out, quarantine, etc. Yes, I am hooked on fishkeeping! I
recently purchased a 125-gallon tank that is still in the
box in my fishroom. My wife says I can’t set it up until I
get the downstairs bathroom renovated. Yeah, I know—the
125 would look great in the wall! Thanks for all the help.
I look forward to every issue.
EMAIL By far the best way to communicate with us at TFH is by email. To ensure that we receive your message, avoid the use of account
names and subject lines that are likely to trigger junk filters. Probably the best subject is “Q&A.” Due to the volume of mail, we are unable
to respond personally to all, but every message is read.
If you are writing for some purpose other than submitting a question (submitting an article, for example), feel free to tap on the glass and
send another message if you do not hear back in a reasonable amount of time. Attachments that are not accompanied by an explanatory
message or query are deleted unopened.